We define quantum lens spaces as `direct sums of line bundles' and exhibit
them as `total spaces' of certain principal bundles over quantum projective
spaces. For each of these quantum lens spaces we construct an analogue of the classical Gysin sequence in K-theory. We use the sequence to compute the
K-theory of the quantum lens spaces, in particular to give explicit geometric
representatives of their K-theory classes. These representatives are interpreted as `line bundles' over quantum lens spaces and generically define
`torsion classes'. We work out explicit examples of these classes.

A self Morita equivalence over an algebra B, given by a B-bimodule E, is thought of as a line bundle over B. The corresponding Pimsner algebra O_E is then the total space algebra of a noncommutative principal circle bundle over B. A natural Gysin-like sequence relates the KK-theories of O_E and of B. Interesting examples come from O_E a quantum lens space over B a quantum weighted projective line (with arbitrary weights). The KK-theory of these spaces is explicitly computed and natural generators are exhibited.